Table of Contents

Elastic Transactions

Elastic Transactions are a complementary alternative to traditional transactions, particularly appealing when implementing search structures. Both forms of transactions can safely be combined within the same application. ε-STM implementation is faster than a state-of-the-art software transactional memory in various workloads and with a speedup of 36% on average. It also presents a speedup over lock-based solutions of 89% on average.

ε-STM

ε-STM is the first software transactional memory supporting elastic transactions. Elastic transactions are a variant of the transactional model. Upon conflict detection, an elastic transaction might drop what it did so far within a separate transaction that immediately commits, and initiate a new transaction which might itself be elastic.

Here is the simple API, ε-STM provides to the user:

BEGIN(elastic);

BEGIN(normal);

END;

READ(x);

WRITE(x,v).

The simplicity of using ε-STM comes from the very few information the programmer has to provide. The programmer has to indicate whether his(her) transaction is normal or elastic and no extra-information (i.e., release action, or on-abort-action) is necessary.